Hot-water temperature and pressure relief device



ept. s, 1925.

E. F. DONNELLY HOT WATER TEMPERATURE AND PRESSURE RELIEF DEVICE Filed Jan. 4, 192

flmlja Patented Sept. 8, 1925.

UNITED STATES EDWARD F. DONNELLY, F MALDEN, MASSACHUSETTS.

HOT-WATER TEMPERATURE AND PRESSURE RELIEF DEVICE.

Application filed January 4, 1924. Serial No. 684,415.

To all whom it may concern:

Be it known that I, EDWARD F. DoNNELLY, a citizen of the United States, residing at Malden, in the county of Middlesex and State of Massachusetts, have invented new and useful Improvements in H0t-lVater Temperature and Pressure Relief Devices, of which the following is a specification.

This invention relates to a hot-water temperature and pressure relief device.

The object of the invention is to provide a simple device, which can be directly attached to the top of a hot-water boiler to automatically operate when the pressure in the boiler arrives at a predetermined amount, and also when the temperature in the boiler reaches a predetermined degree, thus providing a twofold security against the explosion of the boiler, either from an excessive pressure or from an excessive temperature.

It is very desirable that a device of the character set forth should be simple and easily attached; compact and capable of being taken apart and repaired by one not particularly skilled in the art.

It is also very desirable that a device of this character should be capable of being di' rectly attached to the top of the boiler.

The device of this invention, in order to secure these ends, consists primarily of a T fitting adapted to be attached to the top of a boiler and connecting with the pipe of a service system, a valve casing with a valve therein, adapted to be attached to the T fitting and said valve being a pressure valve adapted to open and close communication between the fitting and the valve casing, and a pipe projecting into the chamber of said fitting and having. a fusible plug in its inner end, said pipe being connected to ,the atmosphere and the chamber of said valve casing also being connected to the atmosphere.

In the particular embodiment of my invention hereinafter described, the pipe, with the fusible plug in its inner end, which leads out of the fittlng chamber, connects with a branch leading out of the valve chamber casing, which branch may be connected by a pipe to any suitable receptacle.

The device of my invention is so constructed that the valve, which is spring actuated, can be set for any desired pressure, and the device by which it is set is enclosed within a capon the valve casing, so that if desired, the-'said cap can be sealed and prevent the spring-adjusting member from being tampered yvith.

I Referring to the drawings Figure 1 is a front elevation of my improved hot-water temperature and pressure relief device, illustrating the same as connected to a portion of a boiler broken away to save space.

Fig. 2 is a sectional elevation taken on line 2-2, Figure 1.

Fig. 3 is a detail longitudinal sectional elevation of the pipe connections, which have the fusible plug attached thereto and which connect the fitting chamber to the outlet branch of the valve chamber.

Like numerals refer to like parts throughout the several views of the drawings.

In the drawings, 5 is a portion of the top of. a hot-water boiler with an externally screw-threaded outlet 6. 7 is a fitting provided with a'chamber 8 and having two laterally extending branches 9 and 10 internally screw threaded, an upwardly extending branch 11 also internally screw threaded,

and a downwardly extending branch 12 internally screw threaded to engage the outlet 6 of the boiler.

A valve casing 13 is provided with a valve casing chamber 14, the lower end of said valve casing having screw-threaded engagement with a connecting nipple 15, which has screw-threaded engagement at its lower end with an internal screw thread of the fitting 7. The upper end of the nipple 15 is provided with a valve seat 16, upon which a valve 17 is normally seated. The valve 17 is positioned in the chamber 141 and has a stem 18 extending downwardly therefrom and slidable in a cross bar 19 in the nipple 15. Another valve stem 20 extends upwardly from the valve 17 andis slidably mounted in a bearing 21 provided with a head 21 which has screw-threaded engagement with the upper end of the valve casin 13. A spring 22 encircles the stem 20 and %)ears at its upper 100 end against the lower end of the bearing 21 and at its lower end against the upper face of the valve'17.

When the bearing 21 has been screwed downwardly until its head 21 engages the upper end of the casing 13, it is evident that it cannot be screwed down any further and when so screwed down, the spring 22 is compressed to an extent to enable the valve 17 to release the pressure at 130 pounds.

tends latera 1y from the casing 13 and opens out of the valve casing chamber 14. Said branch 24 has an internally screw-threaded boss 25 thereon, with which an elbow 26 has screw-threaded engagement.

A pipe 27 is connected by a union 28 at its upper end to the elbow 26 and at its lower end is connected by a union 29 to a pipe 30 which has screw-threaded engagement at 31 with the fitting 7. The lower end of the pipe 30 projects into the chamber 8 and has a fusible plug 32 therein. The screw-threaded portion 31 of the pipe 30 has screw-threaded engagement with a boss 33 forming a part of the fitting 7.

Pipes not shown in the drawings may have screw-threaded engagement with the branches 9 and 10 and connect with the different fixtures to which it is desired to supply hot water in the usual manner.

The general manner of use and the operation of the device hereinbefore described is as. follows Assuming-the device to be attached to the outlet 6, ,as illustrated in' Figures 1 and 2,

' and that excessive heat develops in the boiler 5, the plug 32 will melt and the heated water will pass, under pressure, through the pipes 30 and 27, elbow 26 and outlet branch 24 to the outer air and to a convenient receptacle provided therefor. If the pressure in t e oiler 5 becomes excessive or exceeds a certain 1 predetermined amount, the valve 17 will move upwardly away from its seat 16 and the heated water will" pass upwardly through the-branch 24 to said receptacle, and in .each of these instances, cold water will automaticall be supplied to .the boiler and disconnected-from the pipe 27 by unscrewing. the union nut' 29 f and the union nut 28, re-

mosphere and-a fusible plug in the inner end in the usua manner, .the construction forsupplyin this cold water not being shown thus'coohng the water. in the boiler and reducing the temperature and the pressure.

assembled, for example,-the pipe 30 maybe 'screwthreadedporti'on 31 thereof from the Y boss 33. The fuse 32 is driven into the end of .the (pipe 30 and the parts are then reas semble.' a

If it is desired-toincreas'eor diminish the pressure onthe spring 22, the cap 23 is removed and the bearing 21 is rotated clockwise or anti-clockwise respectively.

The seat 16 is a ring which may be removed from the nipple 15 and a new seat inserted in its place, the nipple 15 being unscrewed from the valve casing 13 to enable this work to be done.

In addition to the advantages hereinbefore set forth in relation to the device of this invention, it will be seen that the fusible plug 32 being located in the extreme lower end of the pipe 30, and projecting into the chamber of the fitting 7, all of the water which passes out of theboiler and through the branches 9 and 10 to their respective ipes must contact with the lower end of the use 32 and thus will at all times keep the said fuse clear of any accumulations of grease or other dirt, so that the lower end of the fuse is always bright and clean and always ready to be affected by the predetermined temperature at I claim I 1'. A hot-water temperature relief device having, in combination, 'a pipe fitting provided with a chamber and adapted to be connected directly to the main water outlet of a boiler and having an outlet adapted to be connected to the pipeof aservice system, whereby water may pass normally and uninterruptedly from said boiler throii h said fitting to said servicesystem, a pi e eading from said chamber to the atmosp ere and a fusible plug in the innerfend of said pipe.

2. A hot-water temperature relief device having, in combination, a pipe fitting provided with a chamber and adapted to be connected directly to the main water outlet of a boiler and having an outlet adapted to be connected to the pipe of a service system, whereby water may pass normally and uninterruptedly from said boiler. through said fitting to said service system, apipe projecting into said' chamber and leadln to the atmos here and a fusible plug 'in tie inner end 0 said pipe. v v

3. A' hot-water temperature relief device having, in combination, a vided with a chamber and a apted to be con.- nected directly to the-main water outlet of a boiler and having an outlet adapted to'be whereby water may pass normally and unm terruptedlyv from said boiler through said fitting to said servicesystem, a pipe inclined .atan angle to the'med1an line of said fitting and lea ing from'saidchamber to the atof said pipe.

relief. device having, in combination, a pipe fitting provided with a chamber and adapted to be connecteddirectly to'the main water. outlet of a boiler and having an outlet adapted to be connected to the pipe of a which'it should melt.

pipe fitting pro- I 3 connected to the pipe of a service system, It will -'be seen that the different parts of the device of my invention may be easily disservice system, whereby water may p'ass normally and uninterruptedly from said boiler through said fitting to said service system, a pipe leading from said chamber to the atmosphere, a fusible plug inth'e inner end of said pipe, a valve casing provided with a valve chamber and with an outlet orifice leading out of said Valve chamber to the atmosphere, means connecting said valve chamber to said fitting chamber and a valve member in said valve chamber adapted to open and close communication between said chambers and adapted to be opened by a predetermined pressure within the boiler.

5. A hot-water temperature and pressure relief device having, in combination, a pipe fitting provided with a chamber and adapted to be connected directly to the main water outlet of a boiler and having an outlet adapted to be connected to the pipe of a service system, whereby water may pass normally and uninterruptedly from said boiler through said fitting to said service system, a pipe leading fromv said chamber to the atmosphere, a fusible plug in the inner end of said pipe, a valve casing provided with a valve chamber and with an outlet orifice leading from said chamber to the atmosphere, a tubular member connecting the bottom of said valve casing to the top of said fitting, whereby said valve chamber and said fitting chamber are connected together, the upper end of said tubular member constituting a valve seat and a spring-actuated valve member in said valve chamber adapted to open and close communication between said chambers and adapted to be opened by a pre determined pressure within the boiler.

6. A hot-water temperature and pressure relief device having, in combination, a pipe fitting provided with a chamber and adapt ed to be connected directly to the main outlet of a boiler and having an outlet adapted to be connected to the pipe of a service system, whereby water may pass normally and uninterruptedly from said boiler through said fitting to said service system, a valve casing provided with a valve chamber. a lateral tubular branch on said valve casing opening to the atmosphere, a pipe leadin from said fitting chamber into said latera tubular outlet, a tubular member connecting the bottom of said valve casing to the top of said fitting, whereby said valve chamber and said fitting chamber are connected together and a valve member in said valve chamber adapted to open and close communication between said chambers and adapted to be opened by a predetermined pressure within the boiler.

'Z'. A hot-water temperature and pressure relief device having, in combination, a fitting with four branches, each of said branches being internally screw threaded, one or" said branches opening out of the bottom of said fitting and adapted to be fastened to the outlet of a boiler, two of said branches being lateral branches adapted to be connected to the pipes of a service system and a valve casing having a valve chamber, a nipple connectin the bottom of said valve ch amber to a branc on the top of said fitting,

a latterly extending tubular outlet branch opening out of said valve chamber, a valve located in'said valve chamber and adapted to open or close communication between the valve chamber and the fitting chamber and adapted to be opened by excessive pressure within the'boiler, a pipe connected to said fitting chamber and projecting at its lower end into said fitting chamber, a fusible 'plu in the lower end of said pipe, the upper en of said pipe opening into the lateral outlet branch of said valve casing, whereby excessive pressure in said boiler will cause said valve to open and allow the water inthe boiler to pass outwardly through said fitting chamber and valve chamber to the atmosphere and whereby excessive temperature in said boiler will cause said fusible plug to melt and the heated water under pressure to pass outwardly through said pipe. and into said lateraltubular branch.

In testimony whereof I have hereunto my hand.

set

EDWARD F. DONNELLY. 

